Watches fitted with an alarm function and including an alarm time indication mechanism are known. Most of these timepieces include a striking work that is released every twelve hours and whose strike time is indicated by an additional hand. The alarm time may be set by moving the additional hand around the dial using the time-setting stem. One drawback of such timepieces is that it is not possible to set the alarm time more than twelve hours in advance.
GB Patent No. 1397982 discloses a timekeeper with an alarm that can be set twenty-four hours in advance. The dial of this timepiece includes an additional scale that divides the circumference of the dial into twenty-four hours. An alarm hand cooperates with this scale to indicate the selected alarm time. It is thus possible to select the striking time up to twenty-four hours in advance. This prior solution also has drawbacks. The division of the dial into twenty-four hours instead of twelve is unusual and can cause confusion. In such conditions, manipulation errors caused by incorrect reading of the alarm time are possible. Moreover, the fact of indicating the alarm time with a single hand associated with a dial including a large number of divisions means that the alarm time cannot be set with precision.
CH Patent No. 510906 discloses an alarm indicating and releasing device for a timepiece using a twelve-hour dial but that is only released every twenty-four hours. This feature is obtained owing to a cam moving intermittently every twelve hours to activate and deactivate the striking work once every two times. A coloured mark visible through the dial indicates whether the striking work will be released during the next twelve hours or the following twelve hours. The solution proposed by this prior document overcomes some of the aforementioned problems. However, the meaning of the coloured mark is not obvious to a new user. It is doubtful that someone would be able to understand the alarm time setting principle without using the instructions.
It is an object of the present invention to provide an alarm watch including an alarm time indication device that can be set up to twenty-four hours in advance and which is as easy to read as possible.
It is another object of the present invention to provide an alarm watch wherein the alarm time can be set with a high level of precision.